Got an urgent call that needs to overcome virtually infinite gravity? This Question of the Week explores if mobile calls from black holes are possible. Plus, we ask if ploughing up the snow can worsen global warming.

• What happens when two black holes meet? - Podcasts
• Is it possible to make a phone call from a black hole? - Questions
• Curious about Mars... - Podcasts
• Can two black holes merge together if they get close enough to each other? - Questions
• Black holes, as revealed by X-rays - News
• Colliding Black Holes in Pulsar Data - Interviews